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Syrphidae (Diptera) commonly called hoverflies, includes more than 5000 species world-wide. The aim of this study was to address the systematic position of the disputed elements in the intrafamilial classification of Syrphidae, namely the monophyly of Eristalinae and the placement of Microdontini and Pipizini, as well as the position of particular genera ( Nausigaster, Alipumilio, Spheginobaccha). Sequence data from nuclear 28S rRNA and mitochondrial COI genes in conjunction with larval and adult morphological characters of fifty-one syrphid taxa were analysed using optimization alignment to explore phylogenetic relationships among included taxa. A species of Platypezidae, Agathomyia unicolor, was used as outgroup, and also including one representative ( Jassidophaga villosa) of the sister-group of Syrphidae, Pipunculidae. Sensitivity of the data was assessed under six different parameter values. A stability tree summarized the results. Microdontini, including Spheginobaccha, was placed basally, and Pipizini appeared as the sister-group to subfamily Syrphinae. The monophyly of subfamily Eristalinae was supported. The results support at least two independent origins of entomophagy in syrphids, and frequent shifts between larval feeding habitats within the saprophagous eristalines. [ABSTRACT FROM AUTHOR]

The study of functional diversity (FD) provides ways to understand phenomena as complex as community assembly or the dynamics of biodiversity change under multiple pressures. Different frameworks are used to quantify FD, either based on dissimilarity matrices (e.g. Rao entropy, functional dendrograms) or multidimensional spaces (e.g. convex hulls, kernel‐density hypervolumes), each with their own strengths and limits. Frameworks based on dissimilarity matrices either do not enable the measurement of all components of FD (i.e. richness, divergence, and regularity), or result in the distortion of the functional space. Frameworks based on multidimensional spaces do not allow for comparisons with phylogenetic diversity (PD) measures and can be sensitive to outliers. We propose the use of neighbor‐joining trees (NJ) to represent and quantify FD in a way that combines the strengths of current frameworks without many of their weaknesses. Importantly, our approach is uniquely suited for studies that compare FD with PD, as both share the use of trees (NJ or others) and the same mathematical principles. We test the ability of this novel framework to represent the initial functional distances between species with minimal functional space distortion and sensitivity to outliers. The results using NJ are compared with conventional functional dendrograms, convex hulls, and kernel‐density hypervolumes using both simulated and empirical datasets. Using NJ, we demonstrate that it is possible to combine much of the flexibility provided by multidimensional spaces with the simplicity of tree‐based representations. Moreover, the method is directly comparable with taxonomic diversity (TD) and PD measures, and enables quantification of the richness, divergence and regularity of the functional space. [ABSTRACT FROM AUTHOR]